// 封装倒计时逻辑函数
import { ref,computed,onUnmounted } from 'vue'
import dayjs from 'dayjs'
export const useCountDown = ()=>{
// 1. 响应式数据
  const time = ref()
  let timer = null
  const formatTime = computed(()=> dayjs.unix(time.value).format('mm分ss秒'))
// 2. 开启倒计时函数
  const start = (currentTime) =>{
    // 开启倒计时逻辑
    // 每隔一秒减一
    time.value = currentTime
    timer = setInterval(() => {
      time.value--
    }, 1000);
  }
  // 组件销毁时销毁定时器
  onUnmounted(()=>{
    timer && clearInterval(timer)
  })
  return {
    formatTime,
    start
  }
}